Add support for destructuring variable declarations

Change-Id: Ia7f894fb61cfa760e253963ab4815d98103cfd9b
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

1 files changed, 24 insertions, 12 deletions

diff --git a/src/qml/compiler/qv4compilerscanfunctions.cpp b/src/qml/compiler/qv4compilerscanfunctions.cpp
index 3f98d7fd67..c6e792fc45 100644
--- a/src/qml/compiler/qv4compilerscanfunctions.cpp
+++ b/src/qml/compiler/qv4compilerscanfunctions.cpp
@@ -196,18 +196,30 @@ bool ScanFunctions::visit(PatternElement *ast)
     if (!ast->isVariableDeclaration())
         return true;
 
-    if (_context->isStrict && (ast->bindingIdentifier == QLatin1String("eval") || ast->bindingIdentifier == QLatin1String("arguments")))
-        _cg->throwSyntaxError(ast->identifierToken, QStringLiteral("Variable name may not be eval or arguments in strict mode"));
-    checkName(QStringRef(&ast->bindingIdentifier), ast->identifierToken);
-    if (ast->bindingIdentifier == QLatin1String("arguments"))
-        _context->usesArgumentsObject = Context::ArgumentsObjectNotUsed;
-    if (ast->scope == VariableScope::Const && !ast->initializer) {
-        _cg->throwSyntaxError(ast->identifierToken, QStringLiteral("Missing initializer in const declaration"));
-        return false;
-    }
-    if (!_context->addLocalVar(ast->bindingIdentifier, ast->initializer ? Context::VariableDefinition : Context::VariableDeclaration, ast->scope)) {
-        _cg->throwSyntaxError(ast->identifierToken, QStringLiteral("Identifier %1 has already been declared").arg(ast->bindingIdentifier));
-        return false;
+    QStringList names;
+    ast->boundNames(&names);
+
+    for (const QString &name : qAsConst(names)) {
+        if (_context->isStrict && (name == QLatin1String("eval") || name == QLatin1String("arguments")))
+            _cg->throwSyntaxError(ast->identifierToken, QStringLiteral("Variable name may not be eval or arguments in strict mode"));
+        checkName(QStringRef(&name), ast->identifierToken);
+        if (name == QLatin1String("arguments"))
+            _context->usesArgumentsObject = Context::ArgumentsObjectNotUsed;
+        if (ast->scope == VariableScope::Const && !ast->initializer) {
+            _cg->throwSyntaxError(ast->identifierToken, QStringLiteral("Missing initializer in const declaration"));
+            return false;
+        }
+        const Context::Member *m = nullptr;
+        if (_context->memberInfo(name, &m)) {
+            if (m->isLexicallyScoped() || ast->isLexicallyScoped()) {
+                _cg->throwSyntaxError(ast->identifierToken, QStringLiteral("Identifier %1 has already been declared").arg(name));
+                return false;
+            }
+        }
+        if (!_context->addLocalVar(name, ast->initializer ? Context::VariableDefinition : Context::VariableDeclaration, ast->scope)) {
+            _cg->throwSyntaxError(ast->identifierToken, QStringLiteral("Identifier %1 has already been declared").arg(ast->bindingIdentifier));
+            return false;
+        }
     }
     return true;
 }